On-Chip Arrayed Waveguide Grating Interrogated Silicon-on-Insulator Microring Resonator-Based Gas Sensor

We demonstrate on-chip interrogation of a silicon-on-insulator microring resonator-based gas sensor with a compact arrayed waveguide grating (AWG) spectrometer. A 200-GHz silicon-on-insulator AWG with strongly overlapping output channels is used to interrogate a microring resonator sensor response for 100-1000 ppm ethanol vapor concentrations. Such an integrated sensor-interrogator approach is presented as an alternative to the current costly and off-chip read-out systems used for ring resonator-based sensors.